Summary of Significant Accounting Policies: (Policies)	9 Months Ended
Sep. 30, 2020
Accounting Policies [Abstract]
Basis of Accounting, Policy	Nature of Operations: American States Water Company (“AWR”) is the parent company of Golden State Water Company (“GSWC”), Bear Valley Electric Service, Inc. ("BVESI"), and American States Utility Services, Inc. (“ASUS”) (and its subsidiaries, Fort Bliss Water Services Company (“FBWS”), Terrapin Utility Services, Inc. (“TUS”), Old Dominion Utility Services, Inc. (“ODUS”), Palmetto State Utility Services, Inc. (“PSUS”), Old North Utility Services, Inc. (“ONUS”), Emerald Coast Utility Services, Inc. ("ECUS"), and Fort Riley Utility Services, Inc. ("FRUS")). The subsidiaries of ASUS are collectively referred to as the “Military Utility Privatization Subsidiaries.” On July 1, 2020, GSWC completed the transfer of the electric utility assets and liabilities from its electric division to BVESI, a separate legal entity and wholly owned subsidiary of AWR (Note 12). This reorganization is not expected to result in any substantive changes to AWR's operations and business segments. AWR, through its wholly owned subsidiaries, serves over one million people in nine states. GSWC and BVESI are both California public utilities, with GSWC engaged in the purchase, production, distribution and sale of water throughout California serving approximately 261,500 customer connections, while BVESI distributes electricity in several San Bernardino County mountain communities in California serving approximately 24,500 customer connections. The California Public Utilities Commission (“CPUC”) regulates GSWC’s and BVESI's businesses in matters including properties, rates, services, facilities, and transactions between GSWC, BVESI, and their affiliates. ASUS, through its wholly owned subsidiaries, operates, maintains and performs construction activities (including renewal and replacement capital work) on water and/or wastewater systems at various U.S. military bases pursuant to initial 50-year firm fixed-price contracts. These contracts are subject to annual economic price adjustments and modifications for changes in circumstances, changes in laws and regulations and additions to the contract value for new construction of facilities at the military bases. There is no direct regulatory oversight by the CPUC over AWR or the operations, rates or services provided by ASUS or any of its wholly owned subsidiaries. Basis of Presentation: The consolidated financial statements and notes thereto are presented in a combined report filed by two separate Registrants: AWR and GSWC. References in this report to “Registrant” are to AWR and GSWC, collectively, unless otherwise specified. Certain prior period amounts have been reclassified on the statements of cash flows to conform to current year presentation. AWR owns all of the outstanding common shares of GSWC, BVESI, and ASUS. ASUS owns all of the outstanding common stock of the Military Utility Privatization Subsidiaries. The consolidated financial statements of AWR include the accounts of AWR and its subsidiaries. These financial statements are prepared in conformity with accounting principles generally accepted in the United States of America ("GAAP"). Intercompany transactions and balances have been eliminated in the AWR consolidated financial statements. The consolidated financial statements included herein have been prepared by Registrant, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The December 31, 2019 condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by GAAP. The preparation of the consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. In the opinion of management, all adjustments consisting of normal, recurring items, and estimates necessary for a fair statement of the results for the interim periods have been made. It is suggested that these consolidated financial statements be read in conjunction with the consolidated financial statements and the notes thereto included in the Form 10-K for the year ended December 31, 2019 filed with the SEC.
GSWC's Related Party Transactions and Financing Activities	Related Party Transactions and Financing Activities: GSWC, BVESI, and ASUS provide and/or receive various support services to and from their parent, AWR, and among themselves. GSWC has also allocated certain corporate office administrative and general costs to its affiliates, BVESI and ASUS, using allocation factors approved by the CPUC. GSWC allocated corporate office administrative and general costs to BVESI of approximately $643,000 during the three months ended September 30, 2020. GSWC allocated corporate office administrative and general costs to ASUS of approximately $1.2 million during each of the three months ended September 30, 2020 and 2019, and approximately $3.8 million and $3.5 million during the nine months ended September 30, 2020 and 2019 respectively. AWR borrows under a credit facility, which expires in May 2023, and provides funds to GSWC and ASUS in support of their operations. The interest rate charged to GSWC and ASUS is sufficient to cover AWR’s interest expense under the credit facility. In March 2020, AWR amended the credit facility to temporarily increase the borrowing capacity by $35.0 million to $260.0 million until December 31, 2020, at which point the commitment will be reduced to $200.0 million. As of September 30, 2020, there was $89.0 million outstanding under this facility. Effective July 1, 2020, BVESI put in place and has access to a 3-year, $35 million revolving credit facility. Under the terms of the credit agreement, BVESI has the option to request an increase in the facility by an additional $15 million. As of September 30, 2020, there was $3.0 million outstanding under this facility. On July 8, 2020, GSWC completed the issuance of unsecured private placement notes totaling $160.0 million. In connection with this financing, GSWC issued (i) $85.0 million aggregate principal amount of Series A Senior Notes at a coupon rate of 2.17% due July 8, 2030, and (ii) $75.0 million aggregate principal amount of Series B Senior Notes at a coupon rate of 2.90% due July 8, 2040. Interest on the Notes is payable semiannually. The Notes are unsecured and rank equally with GSWC’s unsecured and unsubordinated debt. GSWC may, at its option, redeem all or portions of the Notes at any time upon written notice, subject to payment of a make-whole premium based on 50 basis points above the applicable treasury yield. Under the terms of the Notes, GSWC may not incur any additional indebtedness or pay any distributions to its parent, AWR, if after giving effect thereto, GSWC would have a total indebtedness to capitalization ratio of more than 0.6667:1.00. In addition, GSWC may not incur any additional indebtedness if, after giving effect thereto, it would have a total indebtedness to earnings before interest, taxes, depreciation and amortization ratio greater than 8.00:1.00. GSWC used the proceeds from the new notes to pay down a majority of the intercompany borrowings from AWR parent. AWR used the proceeds received from GSWC to pay down borrowings on its revolving credit facility. Following the issuance of the notes and effective July 15, 2020, AWR reduced the aggregate borrowing capacity of its credit facility to $200.0 million pursuant to the terms of that credit facility agreement. The CPUC requires GSWC to completely pay down all intercompany borrowings from AWR within a 24-month period. The next 24-month period in which GSWC is required to completely pay down its intercompany borrowings ends in November 2020. As a result, GSWC’s intercompany borrowings of $34.1 million as of September 30, 2020 have been classified as a current liability on GSWC’s balance sheet.
COVID-19 Impact	COVID-19 Impact: GSWC, BVESI, and ASUS have continued their operations given that their water, wastewater, and electric utility services are deemed essential. The Company's responses take into account the guidance provided by federal, state, and local health authorities and other government officials to the COVID-19 pandemic. Some of the actions taken by GSWC and BVESI include: (i) suspending, at least through April 2021, service disconnections for nonpayment pursuant to CPUC orders; (ii) increasing the number of employees telecommuting; and (iii) delaying some capital improvement projects at the water utility services business. Thus far, the COVID-19 pandemic has not had a material impact on ASUS's operations. The pandemic has caused significant volatility on financial markets, resulting in significant fluctuations in the fair value of plan assets in GSWC's pension and other retirement plans. Management believes this volatility may continue throughout the pandemic. Due to expected future credit losses on utility customer bills, Registrant has increased its allowance for doubtful accounts as of September 30, 2020. However, the CPUC has authorized GSWC and BVESI to track incremental costs, including bad debt expense in excess of what is included in their respective revenue requirements, incurred as a result of the COVID-19 pandemic in a Catastrophic Event Memorandum Account ("CEMA") to be filed with the CPUC for future recovery. GSWC and BVESI have recorded a total of approximately $1.4 million in the CEMA accounts as regulatory assets, as the Company believes such amounts are probable of recovery.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements: Accounting Pronouncements Adopted in 2020 In June 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, and issued further guidance in November 2018 and May 2019 related to the impairment of financial instruments, effective January 1, 2020. The new guidance provides an impairment model, known as the current expected credit loss model, which is based on expected credit losses rather than incurred losses over the remaining life of most financial assets measured at amortized cost, including trade and other receivables. For the three and nine months ended September 30, 2020, Registrant has increased its allowance for doubtful accounts for utility customer accounts receivable by $871,000 and $1.9 million, respectively, due to Registrant's current estimate of the expected associated economic impact of the COVID pandemic (see Note 10). Accounting Pronouncements to be Adopted in Future Periods In August 2018, the FASB issued ASU 2018-14, Compensation-Retirement Benefits—Defined Benefit Plans-General (Subtopic 715-20): Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans. This ASU removes disclosures to pension plans and other retirement plans that no longer are considered cost beneficial, clarifies the specific disclosure requirements and adds disclosure requirements deemed relevant. This ASU is effective for fiscal years ending after December 15, 2020 and will be applied by Registrant on a retrospective basis to all periods presented. Registrant does not believe the ASU will have a material impact on the Company's financial statements and disclosures. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740)—Simplifying the Accounting for Income Taxes. The amendments in this update simplify the accounting for income taxes by removing certain exceptions and clarifying certain requirements regarding franchise taxes, goodwill, consolidated tax expenses, and annual effective tax rate calculations. The ASU is effective for fiscal years beginning after December 15, 2020. Early adoption is permitted. Registrant does not believe this ASU will have a material impact on its financial statements.

Summary of Significant Accounting Policies: (Policies)

9 Months Ended

Sep. 30, 2020

Nature of Operations: American States Water Company (“AWR”) is the parent company of Golden State Water Company (“GSWC”), Bear Valley Electric Service, Inc. ("BVESI"), and American States Utility Services, Inc. (“ASUS”) (and its subsidiaries, Fort Bliss Water Services Company (“FBWS”), Terrapin Utility Services, Inc. (“TUS”), Old Dominion Utility Services, Inc. (“ODUS”), Palmetto State Utility Services, Inc. (“PSUS”), Old North Utility Services, Inc. (“ONUS”), Emerald Coast Utility Services, Inc. ("ECUS"), and Fort Riley Utility Services, Inc. ("FRUS")). The subsidiaries of ASUS are collectively referred to as the “Military Utility Privatization Subsidiaries.” On July 1, 2020, GSWC completed the transfer of the electric utility assets and liabilities from its electric division to BVESI, a separate legal entity and wholly owned subsidiary of AWR (Note 12). This reorganization is not expected to result in any substantive changes to AWR's operations and business segments. AWR, through its wholly owned subsidiaries, serves over one million people in nine states.

GSWC and BVESI are both California public utilities, with GSWC engaged in the purchase, production, distribution and sale of water throughout California serving approximately 261,500 customer connections, while BVESI distributes electricity in several San Bernardino County mountain communities in California serving approximately 24,500 customer connections. The California Public Utilities Commission (“CPUC”) regulates GSWC’s and BVESI's businesses in matters including properties, rates, services, facilities, and transactions between GSWC, BVESI, and their affiliates.

ASUS, through its wholly owned subsidiaries, operates, maintains and performs construction activities (including renewal and replacement capital work) on water and/or wastewater systems at various U.S. military bases pursuant to initial 50-year firm fixed-price contracts. These contracts are subject to annual economic price adjustments and modifications for changes in circumstances, changes in laws and regulations and additions to the contract value for new construction of facilities at the military bases.

There is no direct regulatory oversight by the CPUC over AWR or the operations, rates or services provided by ASUS or any of its wholly owned subsidiaries.

Basis of Presentation: The consolidated financial statements and notes thereto are presented in a combined report filed by two separate Registrants: AWR and GSWC. References in this report to “Registrant” are to AWR and GSWC, collectively, unless otherwise specified. Certain prior period amounts have been reclassified on the statements of cash flows to conform to current year presentation. AWR owns all of the outstanding common shares of GSWC, BVESI, and ASUS. ASUS owns all of the outstanding common stock of the Military Utility Privatization Subsidiaries. The consolidated financial statements of AWR include the accounts of AWR and its subsidiaries. These financial statements are prepared in conformity with accounting principles generally accepted in the United States of America ("GAAP"). Intercompany transactions and balances have been eliminated in the AWR consolidated financial statements.

The consolidated financial statements included herein have been prepared by Registrant, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The December 31, 2019 condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by GAAP. The preparation of the consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. In the opinion of management, all adjustments consisting of normal, recurring items, and estimates necessary for a fair statement of the results for the interim periods have been made. It is suggested that these consolidated financial statements be read in conjunction with the consolidated financial statements and the notes thereto included in the Form 10-K for the year ended December 31, 2019 filed with the SEC.

Related Party Transactions and Financing Activities: GSWC, BVESI, and ASUS provide and/or receive various support services to and from their parent, AWR, and among themselves. GSWC has also allocated certain corporate office administrative and general costs to its affiliates, BVESI and ASUS, using allocation factors approved by the CPUC. GSWC allocated corporate office administrative and general costs to BVESI of approximately $643,000 during the three months ended September 30, 2020. GSWC allocated corporate office administrative and general costs to ASUS of approximately $1.2 million during each of the three months ended September 30, 2020 and 2019, and approximately $3.8 million and $3.5 million during the nine months ended September 30, 2020 and 2019 respectively.

AWR borrows under a credit facility, which expires in May 2023, and provides funds to GSWC and ASUS in support of their operations. The interest rate charged to GSWC and ASUS is sufficient to cover AWR’s interest expense under the credit facility. In March 2020, AWR amended the credit facility to temporarily increase the borrowing capacity by $35.0 million to $260.0 million until December 31, 2020, at which point the commitment will be reduced to $200.0 million. As of September 30, 2020, there was $89.0 million outstanding under this facility. Effective July 1, 2020, BVESI put in place and has access to a 3-year, $35 million revolving credit facility. Under the terms of the credit agreement, BVESI has the option to request an increase in the facility by an additional $15 million. As of September 30, 2020, there was $3.0 million outstanding under this facility.

On July 8, 2020, GSWC completed the issuance of unsecured private placement notes totaling $160.0 million. In connection with this financing, GSWC issued (i) $85.0 million aggregate principal amount of Series A Senior Notes at a coupon rate of 2.17% due July 8, 2030, and (ii) $75.0 million aggregate principal amount of Series B Senior Notes at a coupon rate of 2.90% due July 8, 2040. Interest on the Notes is payable semiannually. The Notes are unsecured and rank equally with GSWC’s unsecured and unsubordinated debt. GSWC may, at its option, redeem all or portions of the Notes at any time upon written notice, subject to payment of a make-whole premium based on 50 basis points above the applicable treasury yield. Under the terms of the Notes, GSWC may not incur any additional indebtedness or pay any distributions to its parent, AWR, if after giving effect thereto, GSWC would have a total indebtedness to capitalization ratio of more than 0.6667:1.00. In addition, GSWC may not incur any additional indebtedness if, after giving effect thereto, it would have a total indebtedness to earnings before interest, taxes, depreciation and amortization ratio greater than 8.00:1.00.

GSWC used the proceeds from the new notes to pay down a majority of the intercompany borrowings from AWR parent. AWR used the proceeds received from GSWC to pay down borrowings on its revolving credit facility. Following the issuance of the notes and effective July 15, 2020, AWR reduced the aggregate borrowing capacity of its credit facility to $200.0 million pursuant to the terms of that credit facility agreement.

The CPUC requires GSWC to completely pay down all intercompany borrowings from AWR within a 24-month period. The next 24-month period in which GSWC is required to completely pay down its intercompany borrowings ends in November 2020. As a result, GSWC’s intercompany borrowings of $34.1 million as of September 30, 2020 have been classified as a current liability on GSWC’s balance sheet.

COVID-19 Impact

COVID-19 Impact:

GSWC, BVESI, and ASUS have continued their operations given that their water, wastewater, and electric utility services are deemed essential. The Company's responses take into account the guidance provided by federal, state, and local health authorities and other government officials to the COVID-19 pandemic. Some of the actions taken by GSWC and BVESI include: (i) suspending, at least through April 2021, service disconnections for nonpayment pursuant to CPUC orders; (ii) increasing the number of employees telecommuting; and (iii) delaying some capital improvement projects at the water utility services business. Thus far, the COVID-19 pandemic has not had a material impact on ASUS's operations.

The pandemic has caused significant volatility on financial markets, resulting in significant fluctuations in the fair value of plan assets in GSWC's pension and other retirement plans. Management believes this volatility may continue throughout the pandemic.

Due to expected future credit losses on utility customer bills, Registrant has increased its allowance for doubtful accounts as of September 30, 2020. However, the CPUC has authorized GSWC and BVESI to track incremental costs, including bad debt expense in excess of what is included in their respective revenue requirements, incurred as a result of the COVID-19 pandemic in a Catastrophic Event Memorandum Account ("CEMA") to be filed with the CPUC for future recovery. GSWC and BVESI have recorded a total of approximately $1.4 million in the CEMA accounts as regulatory assets, as the Company believes such amounts are probable of recovery.

Recently Issued Accounting Pronouncements

Recently Issued Accounting Pronouncements:

Accounting Pronouncements Adopted in 2020

In June 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, and issued further guidance in November 2018 and May 2019 related to the impairment of financial instruments, effective January 1, 2020. The new guidance provides an impairment model, known as the current expected credit loss model, which is based on expected credit losses rather than incurred losses over the remaining life of most financial assets measured at amortized cost, including trade and other receivables. For the three and nine months ended September 30, 2020, Registrant has increased its allowance for

doubtful accounts for utility customer accounts receivable by $871,000 and $1.9 million, respectively, due to Registrant's current estimate of the expected associated economic impact of the COVID pandemic (see Note 10).

Accounting Pronouncements to be Adopted in Future Periods

In August 2018, the FASB issued ASU 2018-14, Compensation-Retirement Benefits—Defined Benefit Plans-General (Subtopic 715-20): Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans. This ASU removes disclosures to pension plans and other retirement plans that no longer are considered cost beneficial, clarifies the specific disclosure requirements and adds disclosure requirements deemed relevant. This ASU is effective for fiscal years ending after December 15, 2020 and will be applied by Registrant on a retrospective basis to all periods presented. Registrant does not believe the ASU will have a material impact on the Company's financial statements and disclosures.

In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740)—Simplifying the Accounting for Income Taxes. The amendments in this update simplify the accounting for income taxes by removing certain exceptions and clarifying certain requirements regarding franchise taxes, goodwill, consolidated tax expenses, and annual effective tax rate calculations. The ASU is effective for fiscal years beginning after December 15, 2020. Early adoption is permitted. Registrant does not believe this ASU will have a material impact on its financial statements.